This invention relates generally to the art of surgical suturing, and more particularly to suturing devices and methods which employ surgical staples.
A major time consumer in performing surgery is suturing tissues together. In this regard, when performing heart surgery, implant surgery, and many other types of surgery, surgeons must often anastomos blood vessels to other blood vessels, which procedure is normally performed by laboriously stitching edges of blood-vessel openings together. Because the blood vessels are so small and delicate, this procedure often takes hours to accomplish. The suturing of blood vessels and other organs together often forms a large part of a surgical operation, and this time factor can limit the development of, and use of, certain procedures. It is an object of this invention to provide an assembly and method for suturing tissues together, especially blood vessels and other organs, in a relatively rapid manner, thereby significantly reducing the time required for carrying out complicated surgical procedures.
Many surgical stapling systems have been suggested and, in fact, a few are commercially available. However, such devices are normally too big and cumbersome to be practically used for blood vessel anastomosis. It is therefore another object of this invention to provide a surgical stapling system which is sufficiently delicate in size, shape and opertion that it can be used for blood vessel anastomosis.
It has long been recognized that it is preferable to suture tubular organs such as blood vessels, together with individual, independent, radially-aligned stitches, rather than by using a continuous suturing thread extending circumferentially about the tubular organs. One reason for this is that if a blood vessel, for example, is stitched together with a continuous, circumferential, suture thread and the stitches are pulled tightly during the suturing, it will have a "purse string" effect, which tends to constrict the blood vessel at the point of the suture. This "purse-string" effect is magnified in young patients as the patient and his blood vessels grow, since the continuous suture thread will not allow the vessel's internal size to increase with such growth. Individual, unconnected, radially-aligned stitches placed about blood vessels, on the other hand, will not cause this purse-string effect and will allow blood vessels to grow between the stitches. Another reason individual, radially-aligned, stitches are preferable to circumferential continuous-thread stitches is that the continuous thread stitches tend to restrict blood-flow to isolated tissue positioned radially beyond the suture. In some cases this tissue later dies thereby releasing the suture threads and causing the suture to fail. In spite of these tremendous disadvantages most surgeons still use continuous-thread circumferential stitching for tubular organs because it is much faster than positioning independent, radially aligned stitches about tubular organs. Unfortunately, most prior-art staplers, and/or clamps which have been suggested for tubular organs have the same disadvantages as continous-filament sutures. In this respect, many of these systems involve staples each having a long back section which is positioned circumferentially about a tubular organ and end legs which pass through everted edges of the tubular organ. When the end legs are folded toward the back section to close these staples they squeeze the everted tissue between the staple legs and the back section thereby restricting blood flow across the staples. Often such staples are applied to overlap with one another. Such an arrangement of staples provides a "purse string" effect because the circumferentially positioned back sections do not allow the tubular organs to grow radially and they tend to cut off circulation in isolated everted edges of the tubular organs which are positioned radially outside of the staples. It is therefore an object of this invention to provide a stapling assembly and method which not only reduces the time for suturing but which allows a surgeon to suture tubularly-shaped organs, such as blood vessels, with individual, radially-aligned stitches so as not to constrict the tubularly-shaped organs and not to cut off circulation to portions of everted tissue of the tubularly-shaped organs positioned radially outside of the stitches.
Yet another problem with many staple systems is that each of the staples thereof, when opposite legs thereof are bent against an elongated back section thereof, forms an elongated member. Such a shape sometimes allows tissues of two organs stapled together to slide along the back section of the staple to opposite ends thereof, thereby separating from one another. In other words, the long, rectangular, shape of many prior-art staples, allows two tissues to pull apart, with one tissue moving to one end of the staple, and the other tissue moving to the other end of the staple. Thus, it is an object of this invention to provide a stapling apparatus and method which provides a substantially round staple which cannot, therefore, reorient itself to allow separation of tissues stapled together therewith.
Yet another difficulty with many prior art suturing staple devices is that the staples themselves either allow tissue stapled therewith to work itself loose or they include complicated fastening devices which prevent the opening thereof. It is an object of this invention to provide a stapling apparatus and method having staples which, once they are stapled onto tissue, do not allow the tissue to easily free itself from the staples but which do not involve the use of complicated catches or the like on the staples to hold legs thereof together.